This research is motivated by the observation result in SMKN 1 Arosbaya where many students are still doing remidi that need a new learning media that can improve student learning outcomes. By using trainer kit atmega 16 as a learning media is expected to provide solutions to teachers to improve student learning outcomes. This study aims to produce a learning media that deserves review of aspects of validity, effectiveness, and practicality. This research is a type of development research consisting of 7 steps: (1) potential and problem; (2) completion data; (3) product design; (4) product validation; (5) product revisions; (6) product trial; (7) analysis and reporting. The subjects of this study are students of class X TAV at SMK Negeri 1 Arosbaya. In this research is the trial used is one-shot case study. The results show the feasibility level of the trainer as a medium of learning on the aspects of validity with. Aspects of effectiveness in terms of student learning outcomes. From the final student learning result found th = 10,670> ttable = 1,72 with level of signifikansi 0,05, so it can be concluded that the average of the final learning outcomes of students is greater or equal to KKM. And the practical aspect in terms of student response is falling with the assessment result of 90%. Based on the results of the above research, the learning media based on atmega 16 feasible to be used as one of the supporting learning media.